Calculating Heat Loss from Room with Refrigerator and Heater

[oliverjames]

A room contains 25 kg of air at 100KPa and 10 degree C. The room has a 250-W refrigerator (the refrigerator consumes 250 W of electricity when running) and 1-KW electric resistance heater. During a cold winter day, it is observed that both the refrigerator and the resistance heater are running continuously but the air temperature in the room remains constant. The rate of heat loss from the room during that day is:

I`m having trouble solving this . can anyone please help?

cheers
james

 

[russ_watters]

It's a bit of a trick question, but when you see the trick, it is rediculously easy (that should be a hint...).

 

[oliverjames]

ok . if i omit the room criteria and if i`m taking only the refrigerator data the heat loss to the room would be 1250 Kw. correct me if i was wrong. Thanks . James

 

[russ_watters]

Yep, it really is that easy. Nice! Conservation of energy says that if you're at an equilibrium, the inputs and outputs must be equal.